<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .pure_top {
            width: 100%;
            height: 100px;
            position: relative;
            z-index: -1;
            overflow: hidden;
        }

        .pure_top::after {
            content: '';
            width: 140%;
            height: 100px;
            position: absolute;
            left: -20%;
            top: 0;
            z-index: -1;
            border-radius: 0 0 50% 50%;
            background: linear-gradient(160deg,#1496f1, #E0F0FA);
        }
        .cir{
            width: 200px;
            height: 300px;
            background-color: #B4EEB4;
            border-radius: 0 0 50% 50%;
            transform: scaleY(.3);
        }
    </style>
</head>
<body>
    <div class="pure_top"></div>
    <div class="cir"></div>
</body>
</html>